const fs = require('fs');
const path = require('path');
const readline = require('readline');
//文件名
const fileName = path.join(__dirname,'../','../','logs/','access.log');
//创建read stream
const readStream = fs.createReadStream(fileName);
//创建readLine对象
const rl = readline.createInterface({
    input: readStream
})
let chromeNum = 0;
let num = 0;
//逐行读取
rl.on('line',lineData => {
    if(!lineData){
        return;
    }
    //记录总行数
    num++;
    const arr = lineData.split(' -- ');
    if(arr[2] && arr[2].indexOf('Chrome')>0){
        //累加Chrome的数量
        chromeNum++;
    }
})
//监听读取完成
rl.on('close',()=>{
    console.log('chrome占比为：',chromeNum/num);
})